A heat generating body box housing a refrigeration device is used to refrigerate the inside of a box housing, such as a mobile-phone base station, which is closed while provided with an electronic component generating heat therein.
Recently a heat generation amount from a control board markedly increases with enhanced performance of the electronic component and with greater densities of the electronic components on the control board. With the progress of miniaturization of the box housing for the electronic components, there is a demand for the high performance and miniaturization of the refrigeration device and enhancement of a degree of freedom of a layout that the refrigeration device is installed in either a side surface or a top side of the box housing. For this reason, a method in which a heat pipe having a large heat transfer amount is used while the number of components decreases is well known as a method for refrigerating a refrigeration device (for example, PTL 1).
However, in the heat pipe, refrigerant steam that ascends by boiling and vaporization and refrigerant liquid that descends by condensation and devolatilization move in the same pipe. Therefore, the refrigerants face each other to disadvantageously degrade refrigerant circulation efficiency and heat exchange efficiency. For this reason, an evaporator that boils and vaporizes the refrigerant is separated from a condenser that condenses and devolatilizes the refrigerant. That is, a refrigerant steam pipe that communicates between the evaporator and the condenser is provided in order that the refrigerant boiled and vaporized by the evaporator moves to the condenser. A refrigerant liquid pipe that communicates between the condenser and the evaporator is also provided in order that the refrigerant condensed and devolatilized by the condenser moves to the evaporator. Specifically, there is well known a boiling refrigeration device, in which a refrigerant circuit is formed by the refrigerant steam pipe and the refrigerant liquid pipe and the refrigerant is circulated to efficiently release heat (for example, PTL 2).
The boiling refrigeration device as the heat generating body box housing refrigeration device of the background art will be described below with reference to FIGS. 20A and 20B. FIG. 20A is a front view illustrating the heat generating body box housing refrigeration device of the background art, and FIG. 20B is a side view illustrating the heat generating body box housing refrigeration device.
Boiling refrigeration device 201 is provided in main body box 207, and main body box 207 is partitioned by partition plate 206 to include a high-temperature portion 203 to which high-temperature air 202 vents located in a lower portion of main body box 207 and a low-temperature portion 205 to which low-temperature air 204 vents in an upper portion of main body box 207. Evaporator 209 in which refrigerant 208 is enclosed is disposed in high-temperature portion 203. Evaporator 209 receives the heat from high-temperature air 202 to boil and vaporize refrigerant 208.
Condenser 210 communicating with evaporator 209 is disposed in low-temperature portion 205. In condenser 210, refrigerant 208 boiled and vaporized by evaporator 209 releases the heat to low-temperature air 204, and refrigerant 208 is condensed and devolatilized. Evaporator 209 and condenser 210 communicate with each other by refrigerant steam pipe 211 and refrigerant liquid pipe 212, which pierce the partition plate 206.
Indoor-side blower 213 that blows high-temperature air 202 to high-temperature portion 203 and outdoor-side blower 214 that blows low-temperature air 204 to low-temperature portion 205 are also included. According to the above configuration, refrigerant 208 boiled and vaporized by evaporator 209 moves from evaporator 209 to condenser 210 through refrigerant steam pipe 211 by a density difference. Refrigerant 208 condensed and devolatilized by condenser 210 moves from condenser 210 to evaporator 209 through refrigerant liquid pipe 212 by the density difference. Therefore, refrigerant 208 naturally circulates to release the heat of high-temperature air 202 to low-temperature air 204.
In the heat generating body box housing refrigeration device of the background art, in order to efficiently exert capabilities of condenser 210 and evaporator 209, refrigerant steam pipe 211 and refrigerant liquid pipe 212 are diagonally provided such that the refrigerant evenly circulates to the whole surfaces of condenser 210 and evaporator 209. However, a circulation resistance increases with increasing distance from a point at which refrigerant steam pipe 211 of a header in an upper portion of evaporator 209 is connected toward an opposite corner portion in which the steam pipe is not connected. As a result, unfortunately the refrigerant circulation efficiency is degraded to decrease the heat exchange efficiency.